1. Technical Field
The present application relates to a crown cork closure and closing method.
2. Background Information
Background information is for informational purposes only and does not necessarily admit that subsequently mentioned information and publications are prior art.
The present application relates to a crown cork closure system for containers, for example bottles or glass bottles. The closure system comprises on the inner side thereof, in the region of the shaped ends, a deformable sealing material. The deformable sealing material closes hollow spaces at least in the circumference of the end of the crown cork facing towards the container base.
Crown corks, also known as crown caps, are very common and well-known as closures for containers, for example for drinks bottles made of glass, for example for beer and soft drink bottles. In this situation, these crown corks comprise a circular sheet piece with an edge bent in a crown shape, and a sealing insert. The sealing insert was initially made of cork, which as a compressible intermediate piece provided for the necessary and/or desired sealing tightness between the neck of the bottle and the sheet piece. Nowadays, polyvinylchloride (PVC) or polyethylene (PE) is usually used. In addition, for reasons of protection against corrosion, crown corks are, as a rule, coated with protective lacquers.
The most frequently used type of crown cork has twenty-one prongs, wherein the desirability of the odd number of prongs lies in the fact that they do not stand directly opposite one another, and therefore tilting in the delivery devices is prevented or minimized.
Crown corks are placed onto the containers by means of a closure machine, which, with the aid, for example, of a magnetic punch, guides the crown corks that are delivered and presses them onto the necks of the bottles. At the same time, a cylindrical section lowers down around the crown cork, which essentially ensures or promotes that the jagged edge is bent over, or is seamed around the mouth region of the container.
In some methods for closing containers, crown corks are closed onto the mouth region of a container with the formation of a sealing pressure seat between the closure element and the container. In a first closing phase, a temporary clamp connection is produced, and in a subsequent closing phase, the final sealing pressure seat is produced. In this situation, the temporary clamp connection of the closure element with the container is produced by plastic deformation of the crown cork. Some closure processes comprise, in this situation, a plurality of steps with different, i.e. increasing, closure force. A further crown cork closure system may include a tacking head, which comprises movable pin elements for seaming around the crown cork edge. In this situation, a pneumatic drive device is provided for producing a thrust movement for the tacking head.
In some hygienic devices, the closure of the container takes place in a sterile chamber, which sterile environment is produced by a protective gas.
Even if the method and devices usual for this purpose are in wide use, a problem lies in the fact that, during the filling process, the container mouth is frequently wetted with the product directly before the closing device. Wetting of the container mouth can possibly cause contamination in the hollow space which is present beneath the crown cork teeth which have been positioned and seamed, inasmuch as mold formation takes place. In any event, the spaces beneath the crown cork form a partially open hollow space, in which dirt contamination cannot be avoided. Such contamination is especially undesirable since when a consumer drinks from the bottle, his lips and mouth will come in contact with that area.